I suggest you ...

Add the ability to add episodes to a subscribed podcast by dragging them into the podcast's storage folder.

I have some episodes for podcasts that are no longer available through the podcast's rss feed. I want to be able to add them manually to the storage folder and have them appear with the subscribed podcast episodes.

Please send me an email if you want to continue discussing this (Settings/Feedback)
If you want to change your SD card you just have to copy the existing files into the new SD card and because the episodes were already marked as downloaded the app will know about those files and 'see' them

so basically what you are saying is that if I get a larger SD card for my phone (so that I can hold more episodes on my phone at one time), I will have to add every single one of those episodes into it's own "virtual podcast" depending on the original podcast it came from.

And therefore, have 2x as many "podcasts" listed in my subscriptions meaning instead of being listed as Podcast A, Podcast B, Podcast C, etc. it would now show up as Podcast A, Podcast A, Podcast B, Podcast B, Podcast C, Podcast C, etc. due to the "virtual podcasts" because you are unwilling to find a way for a person to add those episodes back into the podcast episode list from which they came from originally?

I am not trying to find a way to link a file to an episode, I am trying to put episodes back onto my phone into the same list from which they came out of.

As explained before there's no way to link the file you will add with an episode of the podcast.
I'm sorry but I will not add this feature as this will not work. Episodes must be managed from the app. If you want you can manage 'external files' by creating a virtual podcast but that's it.
Thank for your understanding

Part of the reason I am asking about this is because what if I get a larger SD card for my phone and want to put all the older episodes (some of which are no longer available on the RSS feed for the podcast) back onto my phone and not have 2x as many "podcasts" listed since 1/2 of them would be "virtual podcasts" as you say I would have to do.

how would the app know to attach the file/episode to the specific podcast? possibly because it is put into the same folder as the rest of the episodes for that podcast?

like for example, for podcast A, I have saved on my computer 25 episodes that are no longer on the downloadable RSS feed for said podcast. if I put these "files/episodes" back into the same folder on my phone (that I moved the files from in the first place) as the rest of the episodes that are still on my phone, why shouldn't the app recognize them? since they came from that podcast and are still in the format that they were downloaded in.

@mhiggins1979@gmail.comThere's no way to do that. How would the app know how to attach this 'standalone file' to one of the podcast episode?
To create a virtual podcast, press on the main screen + button, select Virtual folder, then select a folder outside of the app storage which contains external files.
You'll find more detail in the FAQs (Settings/FAQs)

why can we not add those episodes directly into the existing folder? it would make it much easier so that way, as anonymous said, we don't have two separate podcasts showing up for the exact same provider. and what if it is not "every single episode" that we want to put back on our phones (or other devices) only certain ones? and btw, how do we create a virtual podcast?

As I mentioned above, I sometimes discover a podcast that has been in production a long time. Say, for example, that it has 250 episodes. Often, only a certain number of those are still in the podcast rss feed. I can still download the others and put them in a folder and add them as a virtual podcast but now I have two different podcasts showing in Podcast Addict for the same podcast.

You will have to create a "Virtual podcast" for that. Basically you select a folder and every file within that folder will be considered as an episode.
But you cannot add those files into the existing podcast folder.